A universal mobile telecommunication system (UMTS) is a broadband, packet based system for the transmission of text, digitized voice, video and multi-media. It is a highly subscribed to standard for third generation wireless devices and is generally based on Wideband Code Division Multiple Access (WCDMA).
In operation of an always-on push service, the disclosure layer of the UE typically sends “keep-alive” data to presence agents required for always-on push applications. In most circumstances, the “keep alive” message is sent as a result of a keep alive timer expiring. When the keep alive timer expires, the UE connects to the universal terrestrial radio access network (UTRAN) and sends a message to the presence agent.
Similarly, at the protocol level in data networks, such as those specified in 3GPP and 3GPP2, certain network boundaries require a signaling message from a UE. This protocol message is usually asynchronous and is no way coordinated with the keep alive timer, or vice versa. Other necessary events also occur periodically.
The problem with the above is that there is an inordinately high electrical current draw in having a radio transmitting and receiving when connecting to the network, sending only a brief data message in a connected state, and then shutting down the radio connection. This is further compounded in networks where the UE does not have control over the latency in tearing down of radio resources when data exchange is completed, such as in a UMTS network.